大黄属的植物亲缘关系、化学成分与疗效间联系性的初步研究

本文通过对大黄属7个组27种植物的初步综合研究,探讨大黄属的植物亲缘关系、化学成分和疗效间存在的联系性。研究结果表明,除拉萨大黄Rheum lhasaense外,本属植物普遍含有蒽醌类衍生物,总蒽醌含量为1～8%。但具有明显泻下作用、符合药用商品大黄标准的种类仅限制在掌叶组Sect.Palmata的植物中,例如掌叶大黄R.palmatum,鸡爪大黄R.palmatum var.tanguticum和药用大黄R.officinale等种类。通过研究,认为符合药用商品大黄的标准还可参考以下一项或数项t存在番泻甙类蒽醌衍生物,测定出一定量的还原型大黄酸和芦荟大黄素,样品中有明显的结合型和游离型大黄酸的存在,在植物形态方面叶子具有不同程度的掌状分裂等。本研究为大黄属植物的资源利用和商品大黄的质量鉴定提供了进一步的科学依据。

A PRELIMINARY STUDY OF THE CORRELATION BETWEEN PHYLOGENY, CHEMICAL CONSTITUENTS AND THERAPEUTIC EFFECTS OF RHEUM SPEICES

Forty-eight samples of the root of the Genus Rheum representing 7 sections and 27 species were analysed for their anthraquinone derivatives, rhaponticin, sennosides and purgative activity.The result shows that there are ubiquitous existence of anthraquinbne derivitives in this genus., except Rheum lhasaense, the total anthraquinone content was 1～8%. By means of TLC, emodin, physcion, and chrysophanol were found to be present nearly in all the species, while rhein and sennoside derivitives seemed to be distributed only in the Sect. Palmata. As for rhaponticin, it is obviously present in sections Rheum, Acuminata and Orbicularia, with a notable absence in sections Palmata, Deserticola, Spiciformia and Nobilia (cf. Tab.1). Twelve species selected from different sections were examined chemically and pharmacologically in more detail (cf. Tab. 2 and 3). It was found that the original plants of the official drugs with obvious purgative effect were merely restricted in the Sect. Palmata, e. g. Rheurn palmatum, R. palmaturn var. tanguticum, R. officinale etc.. Furthermore, one or several of the following criteria may serve as the standard of the official Rhubarb, viz., the presence of sennoside derivitives, the occurrence of the reduced form of rhein and aloe-emodin, existance of a certain amount of rhein, either in free or combined form, while the leaves with any kind of palmate incision may also be used as a morphological criterion.The conclusions obtained may be of value to the resource utilization and drug standardization of Rhubarb.